THE FOOT. 223 



position, turn the point downwards, and apply the greater sur- 

 face behind, to the trochlea of the external condyle. The pa- 

 tella is said to be to the tibia, what the olecranon is to the 

 ulna; and is, therefore, a sort of appendage to it, united by 

 ligament instead of being continuous with it, as is the case with 

 the olecranon. 



SECT. 111.: OF THE FOOT. 



The foot forms the third section of the inferior extremity, and 

 is placed at a right angle to the bones of the leg. The size of 

 its bones varies much in different individuals, depending much 

 upon their modes of life, and dress : it also varies much in the 

 two sexes, being, for the most part, smaller in the female. 

 The foot is oblong, narrower behind than before ; presents one 

 surface above, which is its back, and another below, which 

 is the sole; a posterior extremity called the heel, and an ante- 

 rior extremity called the point; also its internal margin is much 

 thicker, longer and more concave, than the external margin. 



The foot is divided into Tarsus, Metatarsus, and Toes or 

 Phalanges. 



o 



Of the Tarsus, (Tar se.) 



The tarsus forms the posterior half of the foot, and is com- 

 posed of seven distinct bones, which are arranged on a plan, 

 and present features having scarcely a single point of resem- 

 blance with the carpus. These bones are,, the Os Calcis, the 

 Astragalus, the Naviculare, the Cuboides, the Cuneiforme Ex- 

 ternum, Cuneiforme Medium, and Cuneiforme Internum. 



Of the Os Calcis, (Cakaneum.) 



The calcaneum, or heel bone, forms, almost exclusively, the 

 posterior half of the tarsus, and may be readily distinguished 

 by its greater magnitude. Its shape is very irregular. Its 

 greatest diameter is in the length of the foot; it is also thicker 

 vertically than transversely. 



